Intel Pentium 4 670 & Pentium D 820

Comments 1 to 25 of 30

im curious as to whether you forced cpu affinity during the multi-tasking benches?
i've noticed that XP seems to be really crappy at dividing processes between the 2 cores

sandra and BF2 are really good examples of this:
Sandra cpu benchmark is multi-threaded - it uses 100% of both cores
Sandra Mem bandwith benchmark is single-thread but SMP aware - uses 100% of 1 core
BF2 is horribly coded pos :p - it uses 100% of one core then 100% of the other, it alternates between cores

i've noticed this a lot, so when im going to be doing some heavy multi-tasking i usually force te affinity of the 2 apps to different cores, this seemed to make a big difference (it also helps with stability of certain apps, bf2 for instance cant stay connected to a server for more than about 2mins if you dont force the affinity to 1 core or the other :| )

Now Newegg is making my head spin (though that could be because it's 6am and I'm just getting ready to go to bed...) all of the 945p, 945g (one is ATX and one is BTX I think) and 955XE (or whatever letters) chipsets support the dual core LGA procs, right? Either I'm confused or newegg needs to update some compatibility notes.

The 820 seems like a good deal all things said and done. Not for gaming, but for everyday use anyways. I love my A64 for gaming, but I still miss how smooth everything felt with hyperthreading. And dual core pwns hyperthreading. *ponders setting up a flash countdown to me having enough 'spare' cash for an X2*

Originally Posted by bigzIt is based on the Smithfield core, which has the a similar feature set to the Prescott core and comes clocked at 2.8GHz with a 1MB L2 cache for each core - in fact, you could consider the Smithfield core to be two Prescott 1MB cores stuck together on the same die.

Technically its two seperate cores installed on the same packaging; there actually is physical seperation between the two dies. This is pretty significant, as if they were on the same die, communications between the two CPUs wouldnt have to occur over the pins.

In response to your question about anyone gaming at low resolutsion with a good card, I hate to say it, but there is one person I know who insists on playing Counterstrike at no more than 1024x768 on his 6800 GT. ;)

Im surprised no one as of yet has taken an 820 and compared it with a 520 or 620 processor... thus far theres been no test to show exactly HOW much performance difference there is between two cores and hyperthreading at the same clock speeds.

Overall a pretty nice review bigz; you do seem a tad rusty though compared to previous reviews. By the way, do you think you used the word "workhorse" enough on the last page? :D

Originally Posted by RotoSequenceI noticed a mistake on the first page

Technically its two seperate cores installed on the same packaging; there actually is physical seperation between the two dies. This is pretty significant, as if they were on the same die, communications between the two CPUs wouldnt have to occur over the pins.

Presler is what I would call 'two separate cores installed on the same packaging'.

Presler will improve yield because you can pick any two cores and install them on the same packaging. On the other hand, Smithfield requires two good cores to be next to each other on the wafer as they are physically attached.

It is the way that the architecture works - Intel have opted for a shared bus because of the limitations of not having the memory controller on-die. AMD share the memory controller and the HyperTransport bus and the cores are connected before that, Intel's current dual core technology does not allow communication on-die because it still needs to talk to the northbridge (AFAIK).

Originally Posted by RotoSequenceI dont see whats stopping them from putting a millimeter or so's distance between two dies though... are you catching something else visually that I'm not?

They way Intel seal their cores to the substrate requires a few millimetres around the edge of each die. Also, most Intel LGA heatsinks have a small, central copper core so two large cores would have areas outside of the contact area.

A note to Hamish,
It's XP that controls thread assignments. It's entirely buggered and I'd love someone to write a competent third-party piece of software to direct the cores. I've been bitching about this since the advent of HT. ;) Perhaps they'll fix it in longhorn? I won't hold my breath, however...it's why I haven't really seen dual core as all THAT great a thing...I get sick of babysitting my HT, much less an entire damn second core! :) It will improve DRASTICALLY when MS pulls its thumb out and actually starts to develop a bit smarter version of thread prediction/assignment. Not the easiest thing in the world to do, but if they just bothered I'm sure it would show up in no time.

As for the article, great job as usual, biggles, but I agree with the comment about being a little rusty on the pure non-graphics hardware end...may wish to stick to writing with bindi on this topic. You're tackling the whole article the same way you would a GPU, and it's just not quite the same thing. I wish I could explain what it is about it, but the whole thing just feels like I read about a new gfx card as opposed to a CPU line.

Also, info on O/C would be useful...this chip is a lower budget chip in the dual core market...would be nice to see how high it successfully cranks...I'm also concerned about the heat output when you OC dual cores on the same chip. Maybe cover in another article along with the A64 X2? It'd give you a reason to get the chip back, at the very least. ;)

Originally Posted by BindibadgiThey way Intel seal their cores to the substrate requires a few millimetres around the edge of each die. Also, most Intel LGA heatsinks have a small, central copper core so two large cores would have areas outside of the contact area.

Well as each retail boxed processor includes a heatsink, it's safe to say that wouldn't matter in the slightest as Intel is smart enough to make the copper spot wide enough. Yes, smart enough even after saying Prescott is better than Northwood (LIES!). Regardless, half the point of the Integrated Heat Spreader is.. well.. spreading the heat. The other point of course being not cracking the crap out of the core/s from your lacklustre heatsink isntallation skills.

If everyone buys retail, yes, but there are a lot of 3rd party heatsinks on the market and a lot of LGA heatsinks already shipped that people will reuse. Also, there's very little to no space to put the heatspreader ON if they were separated.
More or less the whole point of the heatspreader is not cracking the cores on heatsink installation so Intel doesnt have to deal with RMAs. Like the move to LGA. If anything adding an extra layer of something between heatsink and core inhibits the transition of heat somewhat.
I dont understand why people are trying to justify something that somewhere along the line doesnt fit. Im not an Intel engineer but from those pictures it's easy to imagine something dosent work for it so it was better for them to put it together. Why on earth would they risk potentially loosing twice as much money if every time they have to get two perfect cores, rather than mix and match like at 65nm. The argument "because they are stupid" holds no weight.